157,274 research outputs found

    The State Contingent Approach to Farmers' Valuation and Adoption of New Biotech Crops: Nitrogen-Fertilizer Saving and Drought Tolerance Traits

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    We used a state contingent approach to give a detailed analysis of the uncertainty surrounding seed trait adoption. Our framework emphasizes the role of timing and information in farmers’ adoption decisions. The inherent embeddedness of seed traits results in timing restrictions and the inability of post-planting adjustments, this in turn results in farmers necessarily engaging in a game with nature. Two main types of traits we identify are supplementing traits and stabilizing traits – classification into each category is directly related on the mobility of the production factor the trait intends to substitute. Supplementing traits allow for acting after nature (i.e., ex post) while stabilizing traits are better modeled as acting before nature (i.e., ex ante). The type of trait results in different determinants of the farmers’ WTP function.State Contingent, Genetically Modified, Biotech, Contingent Valuation, Nitrogen Absorption Efficiency, Drought Tolerance, Uncertainty, Seed Trait, Technological Adoption, Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

    Above- and belowground herbivory jointly impact defense and seed dispersal traits in Taraxacum officinale

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    Plants are able to cope with herbivores by inducing defensive traits or growth responses that allow them to reduce or avoid the impact of herbivores. Since above- and belowground herbivores differ substantially in life-history traits, for example feeding types, and their spatial distribution, it is likely that they induce different responses in plants. Moreover, strong interactive effects on defense and plant growth are expected when above- and belowground herbivores are jointly present. The strengths and directions of these responses have been scarcely addressed in the literature. Using Taraxacum officinale, the root-feeding nematode Meloidogyne hapla and the locust Schistocerca gregaria as a model species, we examined to what degree above- and belowground herbivory affect (1) plant growth responses, (2) the induction of plant defensive traits, that is, leaf trichomes, and (3) changes in dispersal-related seed traits and seed germination. We compared the performance of plants originating from different populations to address whether plant responses are conserved across putative different genotypes. Overall, aboveground herbivory resulted in increased plant biomass. Root herbivory had no effect on plant growth. Plants exposed to the two herbivores showed fewer leaf trichomes than plants challenged only by one herbivore and consequently experienced greater aboveground herbivory. In addition, herbivory had effects that reached beyond the individual plant by modifying seed morphology, producing seeds with longer pappus, and germination success

    Identification of domestication-related loci associated with flowering time and seed size in soybean with the RAD-seq genotyping method

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    Flowering time and seed size are traits related to domestication. However, identification of domestication-related loci/genes of controlling the traits in soybean is rarely reported. In this study, we identified a total of 48 domestication-related loci based on RAD-seq genotyping of a natural population comprising 286 accessions. Among these, four on chromosome 12 and additional two on chromosomes 11 and 15 were associated with flowering time, and four on chromosomes 11 and 16 were associated with seed size. Of the five genes associated with flowering time and the three genes associated with seed size, three genes Glyma11g18720, Glyma11g15480 and Glyma15g35080 were homologous to Arabidopsis genes, additional five genes were found for the first time to be associated with these two traits. Glyma11g18720 and Glyma05g28130 were co-expressed with five genes homologous to flowering time genes in Arabidopsis, and Glyma11g15480 was co-expressed with 24 genes homologous to seed development genes in Arabidopsis. This study indicates that integration of population divergence analysis, genome-wide association study and expression analysis is an efficient approach to identify candidate domestication-related genes

    Segregating the effects of seed traits and common ancestry of hardwood trees on eastern gray squirrel foraging decisions

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    The evolution of specific seed traits in scatter-hoarded tree species often has been attributed to granivore foraging behavior. However, the degree to which foraging investments and seed traits correlate with phylogenetic relationships among trees remains unexplored. We presented seeds of 23 different hardwood tree species (families Betulaceae, Fagaceae, Juglandaceae) to eastern gray squirrels (Sciurus carolinensis), and measured the time and distance travelled by squirrels that consumed or cached each seed. We estimated 11 physical and chemical seed traits for each species, and the phylogenetic relationships between the 23 hardwood trees. Variance partitioning revealed that considerable variation in foraging investment was attributable to seed traits alone (27-73%), and combined effects of seed traits and phylogeny of hardwood trees (5-55%). A phylogenetic PCA (pPCA) on seed traits and tree phylogeny resulted in 2 global axes of traits that were phylogenetically autocorrelated at the family and genus level and a third local axis in which traits were not phylogenetically autocorrelated. Collectively, these axes explained 30-76% of the variation in squirrel foraging investments. The first global pPCA axis, which produced large scores for seed species with thin shells, low lipid and high carbohydrate content, was negatively related to time to consume and cache seeds and travel distance to cache. The second global pPCA axis, which produced large scores for seeds with high protein, low tannin and low dormancy levels, was an important predictor of consumption time only. The local pPCA axis primarily reflected kernel mass. Although it explained only 12% of the variation in trait space and was not autocorrelated among phylogenetic clades, the local axis was related to all four squirrel foraging investments. Squirrel foraging behaviors are influenced by a combination of phylogenetically conserved and more evolutionarily labile seed traits that is consistent with a weak or more diffuse coevolutionary relationship between rodents and hardwood trees rather than a direct coevolutionary relationship. © 2015 Sundaram et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

    Aridity gradients shape intraspecific variability of morphological traits in native Ceratonia siliqua L. of Morocco

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    The carob tree (Ceratonia siliqua L.) is a significant fruit tree in the Mediterranean region with cultural, biological, and ecological importance. Despite its importance, intraspecific trait variability (ITV) in carob trees has been largely overlooked in previous studies. Understanding ITV and its relationship with environmental conditions is crucial for conservation and breeding programs. In this study, we investigated the variability of carob pod and seed-related traits across different ecological scales in 25 studied populations in Morocco. Significant differences in morphological traits were observed between carob populations at various ecological levels, and pod-related traits exhibited greater variability than seed traits. Correlation analysis revealed strong associations between carob morphological traits and environmental conditions, with altitude and aridity index playing an influential role. The aridity gradient was strongly related to changes in pod size, seed number, and size, as well as seed yield. Our findings highlight an important ITV reaching 45% at the intra-population level, 36.5% at the inter-geographic level, and 30% at the inter-population level. Overall, this study contributes valuable insights into the ecology and adaptation of carob trees, emphasizing the importance of considering intraspecific variability when studying this remarkable species. This knowledge is critical for addressing the challenges posed by climate change and human activities on the long-term survival and ecological functioning of carob populations

    Research Notes : Correlation among seed yield, seed quality and nutritional traits in soybean

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    Introduction : In the present communication, the information obtained on correlations among 14 traits related to seed yield, seed quality and nu-trition in soybean germplasm has been discussed, The information on the nature of variation for these traits in the above material has been reported earlier (Rana et al., 1981). Materials and methods : The materials and methods were reported earlier by Rana et al. (1981)

    Combining abilities and heterotic groups in Pisum sativum L.

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    The objective of this research was to investigate the use of heterosis and estimates of the general combining ability (GCA) and specific combining ability (SCA) for yield and the yield-related traits for identifying suitable parents and forming heterotic groups for pea- breeding programs. Seventy-six F1 hybrids derived from crosses between nineteen female lines and four male testers were evaluated during two seasons. Estimates of variance due to GCA and SCA effects and their relationship revealed predominantly additive effects for all traits. Parents with higher GCA values were "ZAV20" (female parent) and "ZAV23" (male parent).The cross "ZAV5 x ZAV23" showed the highest value for seed yield. Days to flowering and number of seeds per plot were the variables with the highest values for broad and narrow-sense heritability (0.93 and 0.65, respectively), indicating that these traits are highly heritable. The highest best parent heterosis for seed yield was observed in the "ZAV17 x DDR14" hybrid. Four heterotic groups were formed and validated by estimating the intra and inter group heterosis.Fil: EspĂłsito, MarĂ­a Andrea. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Rosario; ArgentinaFil: Gatti, Ileana. Universidad Nacional de Rosario; ArgentinaFil: Cravero, Vanina Pamela. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Rosario; ArgentinaFil: Lopez Anido, Fernando Sebastian. Universidad Nacional de Rosario; ArgentinaFil: Cointry Peix, Enrique Luis. Universidad Nacional de Rosario; Argentin
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